Lightly spray a 6 quart or larger slow cooker with non-stick cooking spray if desired to make clean up easier. Pour a small layer of salad dressing dressing at the bottom of slow cooker. Place chicken pieces on top of that layer and then season the chicken with salt.
Add all of the fresh spinach to the top of the chicken and push it down so that it all fits in the slow cooker.
Pour the remaining salad dressing over the spinach and chicken.
Cover and cook on HIGH for 4 to 5 hours or until the internal temperature of the chicken reads 165° F on an instant read thermometer.
When it has cooked, and you've checked the temperature of the chicken, add the drained mandarin oranges to the slow cooker. Turn the slow cooker to the WARM setting, recover and let the dish stay warm while you cook rice or pasta on the stove-top to serve with the chicken.
Serve the spinach, mandarin oranges and chicken over the rice or pasta.
Notes
This recipe uses frozen chicken breasts or thighs that are put in the slow cooker still frozen. If you would like to use thawed chicken, reduce the cooking time to 4 hours on HIGH. We do not recommend cooking on the LOW setting for a longer period of time. Nutritional information based on using boneless skinless chicken breasts and the sugar free Maple Farms raspberry vinaigrette salad dressing.